Comparisons of participants (n = 1,157) and nonparticipants (n = 3,411) of the 6-month follow-up; n (%); mean [SD].

+Number ranges for the specific variables from 1,123 to 1,157 (participants) and from 3,236 to 3,411 (nonparticipants) because of missing data.++Data for ASA and surgical field are available for the implementation phase; numbers account to 715 (participants), and 2266 (nonparticipants) because of missing data.a)ASA (American Society of Anesthesiologists) physical status classification: (I) Healthy patient; (II) Mild systemic disease, no functional limitation; (III) Severe systemic disease with definite functional limitation; (IV) Severe systemic disease that is a constant threat to life;b)BSI: Brief Symptom Inventory; GSI: General severity index;c)Visual analogue scale of the EQ-5D, 0 to 100 with higher scores indicating better subjective health;d)WHO-5: World Health Organization 5-item Well-Being Index;e)PHQ-2: Patient Health Questionnaire-4, depression subscale;f)CES-D: Center for Epidemiologic Studies Depression Scale;g)GAD-2: Patient Health Questionnaire-4, anxiety subscale;h)AUDIT: Alcohol Use Disorder Identification Test, AUDIT-C: AUDIT subscore for risky alcohol consumption.